While I am playing Warcraft 3 online sometimes a screen pops up and requires me to "terminate" the program. This is what the screen says.

This application has encountered a critical error:
FATAL ERROR!
Program: c:\program files\warcraft iii\war3.exe
Exception: 0xC0000005 (ACCESS_VIOLATION)at 0018:0E9C2B84
The instruction at '0x0E9C2B84' referenced memory at '0x00000018'
The memory could not be 'written'
Press OK to terminate the application